Safety device for mine-elevators



.1. 1s. BARNETTE, Jn.

SAFETY DEVICE FOR MINE ELEVATORS. APPLICATION men MAR. 16. 1920.

1,398,216. 'Pdtented N0v..22, 1921.

2 SHEETS-SHEET I.

, 29'" o (a 1 :2 /Z L v" --'/2 7 /a 1'. s. BARNETTE, JR-

SAFETY DEVICEJOR MINEELEVATORSQ APPLICATION HLED MAR. I6. 1920.

' 1,398,216. Patented Nov. 22, 1921.

[/7 we Z a/ UNITED fsrarss JOHN S. BARNETTE, J'E., 0F BROUGHTON, PENNSYLVANIA.

SAFETY DEVICE FOR MINE-ELEVATORS.

Specification of Letters Patent.

Fatented Nov. 22, 1921'.

Application filed March 16, 1920. Serial No. 366,318.

T 0 all whom it may concern Be it known that I, JoHN SPENCER BAR- NETTE, J12, a citizen of the United States, residing at Broughton, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Safety Devices for Mine-Elevators; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to a safety device for mine elevators, but is also adapted for elevators of other types. One object of the invention is to provide a safety device having a positive action, and designed to prevent the descent of the car, in the event of the breaking of the cable.

A further object is to provide a device which shall include a plurality of dogs mounted on the car and normally held out of operative position by the tension exerted on the cable, and acting when said tension is released to throw the dogs outwardly under the action of resilient devices into engagement with recesses formed in vertical guides in the elevator shaft.

With the foregoing and other objects in view, the invention consists in the novel construction, combination and arrangement of cooperating elements hereinafter described and claimed. 1

In the accompanying drawings:

Figure 1 is a view of the devicein front elevation as applied to an elevator car.

Fig. 2 shows the operative elements in ele vation, the housing devices for the dogs being in section.

Fig. 3 is a transverse section through the structure forming the elevator shaft, the section being taken on a line intersecting the recesses receiving the dogs, and the operative elements being shown in top plan.

7 Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2.

The car, or the upper portion thereof is designated 10 and the usual vertical guides in the elevator shaft are shown at 12, these guides being provided with recesses 14, located at suitable intervals. The recessed guides form an important feature of the invention, since it has heretofore been usual to employ in mine shafts guides which are engaged by dogs designed to grip the surface. This construction however has proved to be ineffectual for the reason that the dogs are frequently unable to obtain a sufficient hold, and also for the reason that the surface of the guides is materially damaged.

The vertically extending bar 15 is con nected with the cable or cables 16 and is also connected with the links 17 which in turn are pivotally connected at 19 with the shank portion 18 of each dog 20. Housings may be provided as shown at 21.

An element 23 which may be a structural element of cage is provided with a central aperture through which bar 15 passes, and

this bar is encircled by a coil spring 25, the upper end of which bears against the under side of said structural element of the cage. The lower end of the spring may be secured to the bar, or bear against the upper portion of the links 17, the spring being under compression during the normal running of the car, and the tension of the cable serving to hold the dogs in inoperative position.

In order to make more positive the action of the dogs, I provide an additional spring 28, the ends of which abut the inner ends of the shanks of the dogs, this spring being under compression under normal running conditions and expanding suddenly if ten sion is released by the breaking of the cable. This spring 28 is retained in position in view of the tendency of the dogs to move inwardly, or toward the center, due to the pull exerted through the links 17 by the weight of the car. The positive action of the dogs is thus insured, and the positive engagement of the elements with the vertical guides of the shaft is also certain, so that in the event of accident the movement of the car will necessarily be prevented, beyond the point where the first recesses in the path of travel of the car are encountered.

What is claimed is:-

A safety device for a movable body consisting of a plurality of dogs, keepers enspring engaging the inner end portions of bar below said bracket portion engageable both dogs, a bar slidable in said bracket With said links at their highest portions. 10 portion, a cable operatively associated With In testimony whereof I affix my signature said bar above said portion, links pivoted to in presence of two Witnesses.

said dogs disposed above said spring and JOHN S. BARNETTE, JR. normally maintained at an angle to each l/Vitnesses: a other by said cable, said links being pivoted LOUIs S. BARNETTE,

to said bar, and an expansive spring on said NAT KArns. 

